Food dispensing apparatus control system



' a 95* 77 ,1 k u j e/ 63 87 93* 75 H'- Dec. 22, 1953 w. l. BENDZ 63,477

FOOD DISPENSING APPARATUS CONTROL SYSTEM Filed Dec. 18, 1947 WITNESSES: INVENTOR fiiw v 23 h a/a emarffienoz A}. if

BY 7 ATTORNE;

Patented Dec. 22, 1953 FOOD DISPENSING APPARATUS CONTROL SYSTEM Waldemar I. Bendz, Weston, Mass assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa.., a. corporation of Pennsylvania Application December 18, 1947, Serial N 792,505

I 9 Claims.

My invention relates to photo-sensitive apparatus and has particular relation to food dispensing apparatus.

In its specific aspects my invention applies to coin operable machines for dispensing liquids such as beverages. The operation of such a. machine is initiated by the insertion of a coin. Following this event, a cup is deposited on a platform and thereafter a valve is opened and liquid flows into the cup. After the valve has been opened for predetermined time interval, the valve is closed.

In machines constructed in accordance with the teachings of the prior art, the operations following the insertion of the coin occur in sequence at independently determined time intervals. The insertion of the coin initiates the operation of a series of timing relays. One of these releases the cup; another one operates a predetermined time interval later to open the liquid valve; the third operates a predetermined time interval after the opening of the valve to close it.

In spite of the fact that such relays are ordinarily interlocked, difficulties arise in the operation of prior art machines. The liquid valve may be opened before the cup is in place. Under such circumstances, the liquid falls on the platform. Eventually the receptacle for the cup overflows and the flOOl under the machine becomes wet. The relay for closing the valve after it is open may operate too early or too late. In the former eventuality, a customer is dissatisfied; in the latter the liquid is wasted and the overflow wets the fioor in the region of the machine.

it is accordingly 2. specific object of my invention to provide a liquid dispensing machine in which the operations following the insertion of the coin shall be dependent each on the actual completion of the preceding operation.

Another specific object of my invention is to provide a liquid dispensing system in which improper flow of the liquid shall be minimized.

A further specific object or my invention is to provide a liquid dispensing system in which each step in the sequence of operations following the insertion of the coin shall be dependent on the completion of a prior step but the flow of the liquid shall be interrupted after a predetermined time interval if it is not interrupted by the completion or" the cup filling operation.

till another specific object of my invention is to provide a liquid dispensing system in which the iiow of liquid shall be restrained until released by the proper seating of the cup in the cup receptacle.

Still another specific object of my invention is to provide a liquid dispensing system in which the how of liquid shall he stepped either when the liquid reaches a predetermined level in the cup, or in any event, after a predetermined time interval.

A general object of my invention is to provide a food .clispensin system which sh...i operate to satisfy each customer that he has received his moneys Worth in food while the time avoiding any waste of the food.

An ancillary object cl invention is to provide a novel electronic timing syste More specifically stated, it is an 013380;; of my invention to provide a food dispe ng system in which each operation of the sequence iollowing the deposit of the coin, with the exception of the operation stopping the how of food, shall be directly dependent on the completion of the preceding operation, and the operation stopping the flow or" food shall be dependent on the completion of the preceding operation in any event, shall be stopped a predetermined time interval after it is started.

In accordance with my invention, I provide a radiation-responsive mechanism for controlling the operation of the food dispensing machine. In the practice of the specific aspects of my invention, the deposit or the food container in its receptacle following the deposit of ie coin causes a beam of radiated energy to be projected on a radiation-responsive device. The radiation-responsive mechanism causes the food valve to open. When the food in the container reached a predetermined level the radiation linp-inging on the radiation-responsive device is interrupted and the valve is closed. the radiation impinging on the device should not, for any reason, be interrupted a predetermined time interval after the how of food has been initiated, the food valve is in any event closed.

The novel features that consider characteristic of my invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereoi, will be understood from the following description of a specific embodiment when read in connection with the accompanying drawing in which the single figure is a diagrammatic view showing an embodiment of my invention. 7

In the drawing, only those features of a liquid dispensing machine concerned with invention are shown. Such a machine includes switches (not. shown) which are closed only if sufiicient quantities of the liquids to be dispensed are available. Such switches when closed, open the coin slot and render the machine capable of accepting a coin. The machine may be provided with several slots (not shown) for accepting different coins such as nickels, dimes, and quarters. The machine also includes a switch which is momentarily closed by the coin as it moves through the coin slot. The mechanical relationship between the coin switch and the slot is well known in the art, and is not shown in detail. Once a coin is deposited relays (not shown) are energized to prevent deposit of another coin until the operation following the first deposit is completed. The machine also includes pilot lights, and switches for such lights (both not shown), for indicating when it is in proper condition for operation and when it is in operation.

The machine in accordance with my invention includes a light source 3 such as an incandescent lamp from which a light beam is projected through an opening 5 in the cup slot 71' to the region beam or" the cup. When the machine is not operating, the lamp circuit is open. When the coin switch 5 is momentarily closed, the exciting coil of a relay i5 is energized to close the lamp circuit at its lower contact it. Current is also momentarily supplied through the coin switch to a cup-drop motor it. The initial rotation of the motor 3? causes a segmented contact disc It to move relative to a brush 2i.

When the motor i? is at rest the brush 2i engages an insulating segment 23 of the disc E3. The initial movement of the motor ll however advances the disc it so that the brush 2i engages a conducting portion thereof closing a circuit, independent of the coin switch i, through the motor El and through the exciting coil of the initiating relay i5 independently of the momentary coin contact I. The motor continues to rotate and a cup 25 is eventually dropped into the cup receptacle 2?.

When the lamp 3 is energized by actuation of starting relay i5, it projects a light beam into the cup slot "i. When a cup is not present in the cup receptacle, the beam is projected to the opposite wall of the slot 7 and produces no eiiect on the liquid supply mechanism.

The cups 25 in use in liquid dispensing machines are ordinarily composed of waxed paper. Such material is translucent. When a cup 25 is deposited in the cup receptacle 2? of the machine, the light beam impinges on its surface producing a light spot which functions as a secondary light source. The radiation from this source is converged by a suitable lens system 2% on the cathode 3% of a photo-electric cell 33.

The'anode 35 of the cell 33 is connected directly to a control grid 37 of a pentode 39 and the cathode SI of the cell is connected to the cathode di of the pentode through a portion of the winding 53 of the secondary d5 of a supply transformer ill and thru a voltage divider 49. The control grid 3': is also connected through a resistor 5! to the movable tap 53 of the voltage divider 49.

When light does not impinge on the photoelectric cell 33, the cell impedance is high, ordinarily of the order of one hundred megohms. Under such circumstances the grid-to-cathode potential of the pentode 39 is determined by the setting or" the voltage divider 49. The latter is so set that the control grid 31 is at a sumciently negative potential relative to the cathode :3! just to prevent the iiow of appreciable grid current and limit the maximum anode current within the specifications of the tube rating. The other grid electrodes 55 and 57 of the pentode 39 are so connected that under such circumstances the pentode conducts maximum current.

When light emitted from the cup 25 impinges on the cell 33, the latter becomes more conducting. Current ilows through the circuit composed of divider as from slider 53, the winding -33 of transformer 37, cell 33 and resistor 5i. With the transformer polarities as specified, this occurs when the anode 56 is positive. Current flowing through resistor 5% produces a voltage drop across it, with negative polarity at the right, adjacent to grid 3?. This potential across resistor 5! adds the negative grid bias to render the potential of grid 3% more negative than when the cell is not energized. The pentode 33 becomes non-conducting; that is, the current through anode 56 is decreased to a negligible value.

The anode 5t and cathode ii of the pentode 39 are connected in a circuit extending from the upper terminal of a secondary section 59 of the transformer t! through the anode-cathode path of the pentode, a network consisting of a resistor and a capacitor 63 connected in parallel, to the lower terminal of the secondary section 59. When a cup 25 is not present in the receptacle 2'? and the pentode 39 is conductive, the capacitor E3 is charged with its upper plate negative and its lower plate positive. When the cup is deposited in the receptacle and the pentode becomes non-conductive, the capacitor 83 is discharged through the resistor 6!.

The network fii-ii3 is connected between the control grid 55 and the cathode Bl" of a thyratron 69. When the machine is not in operation, the anode circuit of the thyratron 6% is maintained open at an upper contact H of the initiating relay 55. When the initiating relay is energized on the deposit of a coin in the coin slot, this contact is closed and the anode circuit through the thyratron 69 is closed. The thyratron, however, remains non-conductive so long as there is no cup in the cup receptacle 2?, because a negative potential is impressed by the capacitor 63 com nected between its control grid 65 and its cathode 61.

When the capacitor 83 is discharged on the deposit of a cup 25 in the receptacle, potential of grid 65 is reduced to Zero and the thyratron 69 becomes conductive. Current then hows in a circuit extending from the upper terminal of a secondary section it through the contact H of the initiating relay, the anode-cathode path of the thyratron 39, a pair of resistors 55 and ii, the exciting coil or" the liquid valve relay to the lower terminal of the secondary section l3. The liquid valve relay is now actuated energizing the valve circuit and causing the valves and 83 which control the flow of carbonated water and syrup respectively to the cup 25 to open. The liquid valves are of any type known in the dispensing art; their specific structure its optical properties.

aces- 77 erson may endeavor to maintain the flow of liquid into the cup a receptacle of his own by projecting light from a match or a flashlight into cell I provide a timing system to guard as ;.n-t s on eventuality. This. system inu eludes =:l thyratron 85. The anode 8'! of this connect d to the junction of and 5?; the cathode as, to the lower t r .l of the secondary section if which.

supplies anode pot-e al to the first thyratron 39. A pair oi resistors ti and 93 and a voltag divider are connected in parallel wi h. the sisters 55 and and the exciting coil of the valve relay The control grid circuit of thyratron extends from its cathode or r ward, thence down to the parallel circuit of t" r i ii and capacitor led, through capacitor resister and to the grid 57. Capa or iti is charged by energy from secondary winding lot of transfer its tive and its right-h d plate negat e. tential across ital renders the potential of grid negative relative to its cathode and prevents conduction of the timing thyratron 85.

e the thyratron $3 is conductive, curent iioivs through the resistors and ii and exciting coil the relay 1 are potential across the resistor 'i'i exciting coil anode-cathode potential across atron EZOQiVCI, this thyra- (.ined non-conductive because its 1 electrode is biased negative relative to 3.33 cathode by the above-mentioned biasvoltage across capacitor tall.

The positive plate of the biasing capacitor i connected to the lower terminal of the secondary section it through a capacitor 463 shunted by a resistor Hi.

The parallel network, capacitor i and resistor iii, are connected in series with resistor between the slider of dividing resistor and the junction to the lower end of win-ding Prior to starting of the operating cycle depositing a coin in the machine, the potential across resistors iii, 35 and S3 is zero and capacitor S9 is fully discharged through resistor ill. As soon as cup is properly seated, a voltage appears across resistors SI, 95 and equal to the voltage across the exciting coil and resistors '55 and ll. A portion of this voltage, between the slider of dividing resistor 55 and the top of resistor is impressed across the network composed of capacitor its and resistor I03. Positive polarity appears at the slider of resistor '35.

Capacitor the is now charged with positive polarity at its lower plate in this network. Hence, the potential across capacitor 39, initially zero, begins to r" e at the instant thyratron Q33 becomes conducting. The rate at which this potential increases depends upon the value of capacitance lee, resistance 1-33 and the voltage between he slider of resistor (55 and the top of resistor iii. The latter component is adjustable and controls the rate of increase of the voltage across capacitor Hi9.

The grid circuit of thyratron 85 includes the shunt network E39l i I, the bias voltage across capacitor llll and grid resistor as. The polarity of the rising potential across capacitor I99, positive at its lower terminal, opposes that of the steady bias voltage. Thus, the potential of grid at becomes less negative as capacitor I09 charges. After the expiration of a predetermined time intel-val, adjusted by the slider oi resistor tiining thyratron is caused to conduct. This time interval begins the instant valve relay is he'- comes energized and ends when thyratron 85 becomes conducting.

The anode-cathode elements of hyratron 85 are connected across the series he ing of the exciting coil oi valve relay l9 and resistor IT. The voltage drop acr ss these elements of the thyratron during its conduction is relatively low, so that the potential across the exciting coil p cular drops appreciably when thyratron 35 con' This low potential is insufficient to hold the contacts of valve relay I?! closed. valve relay 7:; is efiectively deenergized when thyratron c5 conducts.

By the timing sequence thus described the valve relay (9 is deenergized and flow of liquid is interrupted a predetermined time interval following its initial opening. Accordingly, if the operation of the system becomes defective or a dishonest person attempts to maintain the how of liquid by projecting light from a snatch or flashlight onto the cell 33, the valve relay Ill will open after a predetermined time and interrupt the flow of liquid.

Under normal circumstances, the liquid continues to flow until the light beam is interrupted or deflected and thereafter stops. The motor ll continues to rotate until the brush it engages the insulating segment 23. t this point, the circuits through the motor 3? and the exciting coil of the initiating relay are bro on and the latter are deenergized. The lamp 9 is deenergized and the supply of anode potential to the first thyratron 6S and therefore to the second thyratron 85 is interrupted. The operation of a system may now be initiated by the insertion of another coin.

While I have shown and described certain spe cific embodiments of my invention, other modifications thereof are possible. My invention therefore is not to be limited except in so far as is necessitated by the prior art and the spirit of the appended claims.

I claim as my invention:

1. Apparatus for controlling a food dispensing system including a chambe in whit ood is disposed, said chani having a valve therein through which food may pass and a receiver to be positioned to receive the food W ich passe through said valve; comprising in combination, a relay for controlling the closing and opening of said valve, a radiation actuahle system for c0ntrolling said relay to open valve when said container is positioned to receive said food and a control system for causing said relay to close said valve a predetermined time interval after it is opened.

2. Apparatus for controlling a food dispensing system including a. chamber in wh'ch food is disposed, said chamber having a valve therein through which food may pass and a receiver to be positioned to receive the food which passes through said valve; comprising in combination, a relay for controlling the closing and opening of said valve, a radiation actuable system for controlling said relay to open said valve when said container is positioned to receive said food and to close said valve when a predetermined quantity of food is deposited in said receiver, and a control system for causing said relay to close said valve independently of the quantity of food in said receiver, a predetermined time interval after said valve is opened.

3. Apparatus for controlling a food dispensing system including a container and means for projecting food into said container; comprising in combination, meansfor projecting a beam of radiant energy on said container, means responsive to the resultant beam of radiant energy emitted by said container when it is in a position to receive said food for turning said projecting means on and responsive to the interruption of said resultant beam when the food in said container is at a predetermined level to turn said projecting means off, and means for turning said projecting means off after a predetermined time interval independently of the quantity of food in said container.

4. In combination a first electric discharge device, a second electric discharge device, said second device having an anode, cathode and control electrode, means for rendering said first discharge device conductive, means, responsive to said first discharge device when it is conductive, for supplying potential between said anode and cathode, and means for supplying a potential between said control electrode and said cathode which varies so that said second device is rendered condi ve a predetermined time interval after said first device is rendered conductive.

5. In combination a first electric discharge device, a second electric discharge device, said second discharge device having an anode, cathode and control electrode, means for rendering said first discharge device conductive, means, responsive to said first discharge device when it is cond ctive, for supplying potential between said anode cathode, and means, responsive to said first device when it is conductive, for supplying a potential between said control electrode and said cathode which varies so that said second device is rendered conductive a predetermined tim interval after said first device is rendered conductive.

6. In combination a first electric discharge device; an impedance in circuit with said first device; so as current flows through said impedance wh it flows through said device; a second electric discharge, said second device having a plurality pri cipal electrodes and a control e ctrode, said sedance being connecting between prir'upal electrodes; and a reactive impedance in circuit with said first device so that current flows through said reactive impedance when it flows through said first device, said reactive impedance being connected between said control electrode and one of said principal electrodes.

'7. In combination a first electric discharge device; an impedance in circuit with said first device; so current flows through said impedance when it flows through said device; a second electric discharge, second device having a plurality of principal electrodes and a control electrode, said impedance being connecting between said principal electrodes; a reactive impedance in circuit with said first device so that current flows through said reactive impedance when it flows through said first device, said reactive impedance being connected between said control electrode and one of said principal electrodes, and an adjustment for setting the current flow to said reactive impedance to a value such that energy builds up in said reactive impedance at a rate such that said second device is rendered conductive a predetermined time interval after said first device becomes conductive.

8. In combination a first electric discharge device; an impedance in circuit with said first device; so that current flows through said impedance when it flows through said device; a second electric discharge, said second device having a plurality of principal electrodes and a control electrode, said impedance being connecting between said principal electrodes; a reactive impedance in circuit with said first device so that current flows through said reactive impedance when it flows through said first device, said reactive impedance being connected between said control electrode and one of said principal electrodes, and means for rendering said first device conductive, said second device becoming conductive a time interval after said first device becomes conductive which is dependent on the magitude of said reactive impedance.

9. In combination a first electric discharge device; an impedance in circuit with said first device; so that current fiOWS through said impedance when it fiows through said device; a second electric discharge, said second device having a plurality of principal electrodes and a control electrode, said impedance being connecting be tween said principal electrodes; a reactive impedance in circuit with said first device so that current fiows through said reactive impedance when it fiows through said first device, said reactive impedance being connected between said control electrode and one of said principal electrodes, means for rendering said first device conductive, said second device becoming conductive a time interval after said first device becomes conductive which is dependent on the magnitude of said reactive impedance, and means for discharging the energy in said reactive impedance independently of said second device.

WALDEMAR I. BENDZ.

References Sited in the file of this patent UNITED STATES PATENTS 

